Ozone Pollution

On October 1, 2015, EPA strengthened the National Ambient Air Quality Standards (NAAQS) for ground-level ozone to 70 parts per billion (ppb), based on extensive scientific evidence about ozone’s effects on public health and welfare. The updated standards will improve public health protection, particularly for at-risk groups including children, older adults, people of all ages who have lung diseases such as asthma, and people who are active outdoors, especially outdoor workers. They also will improve the health of trees, plants and ecosystems.

This page contains a variety of fact sheets and other documents that are supplementary to the October 2015 revision for the 2008 Ozone National Ambient Air Quality Standards (NAAQS).

This fact sheet outlines the challenges of addressing ozone pollution in some areas of California, along with the work the state and federal government is doing to help address sources of ozone-forming pollution.

This fact sheet describes the Advance Program, a collaborative effort by EPA, states, tribes and local governments to encourage emission reductions to help attainment areas continue to meet standards for ozone and fine particle pollution.